Humidifier



June l5, 1965 Filed Jan. 25,' 1961 c. HoTc'HKlss E'rAl. 3,189,328

fNvENToRs CuFFoRD HoTcHmss Louknes V. Mc C ARTY ATTQRNELY c. HoTcHKlss ETAL 3,189,328

June 15, 1965 HUMIDIFIER Filed Jan. 25, 1961 4 Sheets-Sheet 2 [NX/EDITORS F"| CJ. 3 CLIFFORD HomruussI LouRDes V. McCARTY ATTORNQY VJune '15, 1965 c. Ho'rcHKlss ETAL HUMIDIFIER 4 Sheets-Sheet 3 Filed Jam.4 25. i961 F INVENTORS' ma. 9 CUFFORD HoTcH\ \sS L 'URDESV Mc ATToRNeY June 15, 1965 c. Ho'rcHKlss ETAL 3,189,323

HUMIDIFIER l 4 Sheets-Sheet 4 Filed Jan. 23, 1961 CUFFO'RD HoTcHms's Lou asVMc A BY A-r-roaxwav United States Patent O 3,189,323 HUMIDIFIER Cliord Hotchkiss and Lourdes V. McCarty, Milwaukee, Wis., assignors to Controls Company of America, Schiller Park, Ill., a corporation of Delaware Filed Jian. 23, 196i, Ser. No. 84,162 3 Claims. (Cl. 261-2S) This invention relates to humidhiers for hot air heating systems.

Most humidifier installations do not prov-ide a sutlicient rate of evaporation to raise the humidity to the desired level within the space being heated. Even in humidifier installations which are initially capable of providing suffi* cient humidity, the efficiency of evaporation is soon irnpaired by 1irning" which is the result of evaporation of Water on the evaporating surfaces, leaving the minerals present in the water on the surfaces. In order to increase the evaporating capacity of the humidifier, larger units are used which are capable of raising the humidity level to a point where condensation will appear on the windows of the space being treated. These units cannot generally be completely shut down because the evaporating surface and reservoir remain in the hot air stream. Shut down is not a serious problem when the humidifier does not have adequate capacity to produce sufficient humidity, or has become inefiicient because of liming, but whe-re the humidifier has sufficient capacity to overproduce, then the windows and walls will condense the moisture resulting in objectionable sweating.

The primary object of the present invention is to provide a humidifier Ywhich reduces liming to a minimum.

Another `object of the present invention is to provide a humidifier of high capacity in a small size.

These objects are attained by rotating a single screen or a series of screens partly through a water reservoir and partly through the hot air ducts in a heating system. As the screens rotate and water is evaporated, the mineral content 'of the water in the reservoir will rise. To reduce liming to a minimum under these conditions, a novel wasting water77 system is used to remove water from the reservoir to keep the mineral content down.

Other objects and advantages will be pointed out in, or be apparent from, the specification and claims, as will obvious modifications of the single embodiment shown in the drawings, in which:

FIG. l is a side elevation of the humidifier partly broken away to `show the screens;

FIG. 2 is taken on line 2-2 of FIG. 1 showing an end view .of the humidifier;

FIG. 3 is taken on line 3 3 of FIG. l showing the humidifier in a hot ai-r duct;

FlG. 4 is taken on line 4--4 of FIG. 1 showing the position of the scoops in the humidifier;

FIG. 5 is atop view of the humidifier showing the drive system;

FIG. 6 is similar to FIG. 4 showing the position of the scoop as it enters the water reservoir;

FIG. 7 shows the position of the scoop as the inlet reaches the top of the water in the reservoir;

FIG. 8 shows the scoop rising up with the water entrapped therein; Y

FIG. 9 shows the scoops repeating the cycle;

FIG. 10 is a side elevation of a modified form of humidifier using a cylindrical type screen evaporator;

FIG. 11 is taken on line 11-11 of FIG. l() showing a front elevation of the cylindrical type humidifier; and

FIG. 12 shows the air path through the cylindrical type humidifier.

As seen in the drawings, the humidilier includes a number of screens 10 mounted to rotate with shaft 12 with the lower portion of the screens passing through Water resiz Patented June l5, li

ICC

ervoir 14. The reservoir is secured to one of the hot air ducts 16 of a heating system with the upper portion of the screen rotating through the duct. The shaft is provided on one end with stub shaft 18 which rides in slot 2@ in bracket Z1 and at the other end with gear 22 which rides on gears 24 and 26. The ends of the shaft abut brackets 21 and 23 holding the screens in position. The screens are rotated slowly by motor 28 driving gear 22 through gear 24. With this arrangement, the screens rotate through the reservoir and carry water into the flow path of the hot air in the duct for evaporation. The shaft and screens can be easily lifted out of the reservoir for replacement or repair by merely lifting the stub shaft clear of the slot and gear 22 off of gears 24 and 26.

The water level Within the reservoir is maintained at a constant level by a conventional iioat type supply tank 3) connected to the reservoir by pipe 32. As pointed out above, evaporation of the water on the screens tends to increase the mineral content of the water in the reservoir. In order to maintain la desired mineral concentration in the water to reduce to a minimum the tendency to deposit and lime the reservoir, `a novel bucket arrangement 34- is used to bail water from the reservoir, in effect wasting some of the water in the reservoir, so that more water is supplied to the reservoir than is evaporated. Buckets 36, 36 are mounted to rotate with shaft 12 and are open at the forward end forming scoops which move through the reservoir entrapping a portion of the water. As the buckets rotate out of the water, the Water level rises in the buckets until it flows out through outlet tti into pan 42 and out through drain pipe de. The removal of water from the reservoir having a high mineral content and replacing this Water with relatively low mineral content water keeps the mineral content at a level which reduces to a minimum the tendency of the minerals to deposit out and lime the reservoir. Since the mineral content of the water in the reservoir is kept low, any minerals which may deposit on the screens due to evaporation, either during rotation of the screens or when the screens are at rest, will be dissolved when the screen passes through the water in the reservoir.

As seen in the drawings, this humidier is a complete package which can be easily attached to any hot air system by merely cutting a panel from the bottom of a hot air duct and attaching the reservoir to the duct. The humidifier can be shut down by stopping the rotation of the screens, which is generally satisfactory for complete shut down, except where the reservoir is installed too close to the plenum, causing the reservoir water to boil so that evaporation continues.

This system is not satisfactory for installation in a duct having a high velocity ow of hot air, since the water will be blown off of the screens, evaporating the water and leaving the minerals entrained in the air stream. The minerals will be dried by the hot air and blown into the space being heated in the form of dust. This problem can be overcome by using the system shown in FIGS. l0, ll and 12, where an auxiliary duct 50 is secured to hot air duct 52 having inlet 54 through which hot air is drawn by motor driven fan 56. The hot air is blown against fan blades S8, secured to shaft 59 to slowly turn cylindrical screen 60 so` that the lower portion of the screen passes through water reservoir 62. The air passes through the fan into the center of the screen. and is blocked by plate 63 so that it passes out through the screen (FIG. 12) and then back to the main duct through outlet 64.

The water in the reservoir is main-tained at a constant level 'by float type supply tank A616 through pipe 68. The screen is secured to shaft 59 rotatably supported by .bearing and connected to shaft 59 through reduction gearing 6i. A bucket arrangement '70, similar to that dee, rea,

scribed labove, lis mounted to rot-ate with shaft 59 to scoop water from 'the reservoir. Since any residue left on the -screen after evaporation is Washed off 'the screen by the Water in the reservoir, the continuous changing of the water by the :buckets keeps lthe mineral, level -in Ithe reservoir .below thatfconsidered objectionable. This arrange- Inent is not limited gto -t-he cylindrical type screen but can be modified to use the parallel type screens described prelviouslv Since the normal diow of :air Ithrough the duct 52 will not enter `the auxiliary -duct in sucient volume t0 drive the ffan and the screen, this system has the additional advantage offvprovidingcompleteshut `down when the hu- Qrnid'ity reaches 4a predetermined level in the space being heated .beoause the main -air stream does not `contact the screen or reservoir after the fan has been turned off.

Although but two embodiments of the present invention -ha`ve been illustrated and described, it will :be apparent to those skilled in the art ,that IVarious changes and modiications may be made therein Without departing from the spirit of the yinvention or from the Vscope of the appended claims.

We claim: I, s 1.` In combination with a heating system having a hot airduct, an auxiliary duct having an inlet and outlet in 'communication with said hot air duct, `fanV means for carrying air from said lhotvair duct into said auxiliary duct, evaporator means inthe auxiliary duct, means connected to said evaporator means and loperative to actua-te said evaporator means -in response to operation of said fan means, said evaporator means including `a reservoir and means -for carrying Water from said reservoir into the path of air Aflowing through said auxiliary duct, hailing means `for wasting Water from said reservoir, means for supplying 'fresh Iwater to said reservoir to replace the Water removed so thatthe humidity lof the air tin the hot air duct ismincreased and the water in `sa-id reservoir is contin- 'uouslychange'dduringoperation of sai'd evaporator means.

2. A huni'idier according to claim `1 wherein said reservoir Vis generally -dish'ed and said evaporator means includes lcylindrical screen means and means supporting lI said screen Imeans for rotation by the air drawn through the auxiliary duct by said Ifan means, said cylindrical screen means arranged partially Within said reservoir `and extending exteriorly of the open end thereof Ifor exposure to the air Iflowing Ithrough said auxiliary duct.

3. The humidifier according `to claim 1 wherein sa-id reservior is generally dished and said evaporator means includes `a number of parallel screens and means supporting said screens at the yopen end of said reservo-ir for rotation relative to said reservoir `to carry water Ifrom said reservo-ir into the path of air iiowing through said auxiliary duct.

References Cited by the Examiner UNITED STATES PATENTS 297,476 4/84 Wallace 261-92 1,345,131 6/20 Clewortn 261-92 2,004,108 46/35 Grady 2611-92 2,035,628' 3/36 Whitrrier et al. 2'61--91 X 2,179,470 11/39 Larsen 261-92 X 2,537,211 1/51 Cox. 2,569,512 10/51 Bott-um 126-113 2,709,522 5/55 Osborne 210%36 2,717,957 9/ 55 Ohlheiser 219f20 X 2,766,027 10/56 Herr 26191 2,838,294 6/58 Skerritt 261-104 2,904,995 9/59 Obermaier 73-17 2,967,050 1/61 Geen 2,61-92 3,055,645 9/62 Felderman 261-91 X FOREIGN PATENTS 462,115 12/49 Canada.

154,884 5 03 Germ-any.

5,293 19.10' Great Britain.

149,276 3/55 Sweden.

HARRY B. THORNTON, Primary Examiner. HERBERT L. MARTIN, Examiner. 

1. IN COMBINATION WITH A HEATING SYSTEM HAVING A HOT AIR DUCT, AN AUXILIARY DUCT HAVING AN INLET AND OUTLET IN COMMUNICATION WITH SAID HOT AIR DUCT, FAN MEANS FOR CARRYING AIR FROM SAID HOT AIR DUCT INTO SAID AUXILIARY DUCT, EVAPORATOR MEANS IN THE AUXILIARY DUCT, MEANS CONNECTED TO SAID EVAPORATOR MEANS AND OPERATIVE TO ACTUATE SAID EVAPORATOR MEANS IN RESPONSE TO OPERATION OF SAID FAN MEANS, SAID EVAPORATOR MEANS INCLUDING A RESERVOIR AND MEANS FOR CARRYING WATER FROM SAID AUXILIARY DUCT, BAILING PATH OF AIR FLOWING THROUGH SAID AUXILIARY DUCT, BAILING MEANS FOR WASTING WATER FROM SAID RESERVOIR, MEANS FOR SUPPLYING FRESH WATER TO SAID RESERVOIR TO REPLACE THE WATER REMOVED SO THAT THE HUMIDITY OF THE AIR IN THE HOT AIR DUCT IS INCREASED AND THE WATER IN SAID RESERVOIR IS CONTINUOUSLY CHANGED DURING OPERATION OF SAID EVAPORATOR MEANS. 